Use of next-generation sequencing to detect polymorphism of 11 HLA allele loci in the Chinese Han population and variance from other common and well-documented lists.

The focus of this study was to analyze polymorphisms in the HLA gene at 11 loci in 4845 Chinese Han populations using next-generation sequencing methods, and to compare common and well-documented (CWD) allelic differences between China and other CWD lists. A total of 44 DPB1 alleles, 13 DPA1 alleles, 20 DQA1 alleles and 19 DRB3/4/5 alleles were detected in this study. About 20%-50% of the CWD alleles in China differ from the American Society for Histocompatibility and Immunogenetics and European Federation for Immunogenetics (EFI) data. The revised list of HLA-CWD alleles in the Han population will provide additional data for the update of the IMGT/HLA database and contribute to a better understanding of hematopoietic stem cell transplantation and organ transplantation.

Posttransplant de novo DSA and NDSA affect GvHD, OS, and DFS after haplo-HSCT in patients without pre-existing HLA antibodies of hematological malignancies.

To examine the production time, type, and MFI of post-transplantation de novo HLA antibodies, and their effects on haplo-HSCT outcomes, we retrospectively included 116 patients who were negative for pre-existing HLA antibodies. In total, 322 serum samples from pre-transplantation to post-transplantation were dynamically tested by Luminex and single-antigen bead reagents. Patients were divided into: HLA antibody persistently negative group (group 1), the de novo HLA antibody transiently positive group (group 2), the de novo HLA antibody non-persistently positive group (group 3), and the de novo HLA antibody persistently positive group (group 4). Group 4 included DSA+non-DSA (NDSA) (group 4a) and NDSA (group 4b) groups. The detection rate of de novo HLA antibodies was 75.9% (88/116). The median MFI for de novo HLA antibodies was 2439 (1033-20162). The incidence of II-IV aGvHD was higher in group 2 than in group 1 (52.6% vs 17.9%, P < 0.01); in group 4a than in group 1 (87.5% vs 17.9%, P < 0.001); and in group 4a than in group 4b (87.5% vs 40.0%, P = 0.001). The DFS (37.5% vs 85.7%, P < 0.01) and OS (37.5% vs 85.7%, P < 0.01) of group 4a were lower than those of group 1. The DFS (48.0% vs 85.7%, P < 0.01) and OS (56.0% vs 85.7%, P = 0.03) of group 4b were lower than those of group 1. Multivariate analysis showed that de novo HLA antibody being transiently positive (HR: 5.30; 95% CI: 1.71-16.42, P = 0.01) and persistently positive (HR: 5.67; 95% CI: 2.00-16.08, P < 0.01) were both associated with a higher incidence of II-IV aGvHD. Persistently positive de novo HLA antibodies were a risk factor for reduced DFS (HR: 6.57; 95% CI: 2.08-20.70, P < 0.01) and OS (HR: 5.51; 95% CI: 1.73-17.53, P < 0.01). DSA and NDSA can be detected since 15 days after haplo-HSCT in patients without pre-existing HLA antibodies, and affect aGvHD, DFS, and OS. Haplo-HSCT patients must be monitored for HLA antibodies changes for appropriate preventive clinical management, and we recommend that 1-month post-transplantation is the best test time point.

Establishment of NGS-based HLA 9-locus haplotypes in the Eastern Han Chinese population highlights the role of HLA-DP in donor selection for transplantation.

We collected HLA typing data from 653 families in the Eastern Han Chinese population. HLA-A, B, C, DRB1, DRB3, DRB4, DRB5, DQA1, DQB1, DPA1, and DPB1 (HLA-11 loci) typing of 1781 subjects was performed using a commercial next-generation sequencing (NGS) method in our laboratory. The phasing of haplotypes in each family was determined by Mendelian segregation. Haplotype analysis revealed 1634 different haplotypes among a total of 2230 haplotypes. The predominant haplotype was A*30:01-C*06:02-B*13:02-DRB1*07:01-DRB4*01:03-DQA1*02:01-DQB1*02:02-DPA1*02:01-DPB1*17:01 (HF = 4.04%), followed by A*02:07-C*01:02-B*46:01-DRB1*09:01-DRB4*01:03-DQA1*03:02-DQB1*03:03-DPA1*02:02-DPB1*05:01 (HF = 1.84%) and A*33:03-C*03:02-B*58:01-DRB1*03:01-DRB3*02:02-DQA1*05:01-DQB1*02:01-DPA1*01:03-DPB1*04:01 (HF = 1.48%), accounting for 7.35% of the total. Meanwhile 76.41% of all haplotypes were observed only once or twice (HF < 0.1%). Different from HLA-DRB3/4/5 and DQA1 loci, DP linkage markedly increased haplotype variation by 34.82% based on the 5-locus haplotype. The much weaker linkage disequilibrium (LD) of DQB1-DPB1 indicated the reason. We observed 10 analyzable recombination events, most of which occurred at DP loci. Even with the same common 5-locus haplotype, HLA-DP linkage alters the haplotype diversity and frequency. Analysis of related haplotype assignment and unrelated recipient-donor pairs matching at the 9-locus haplotype revealed that HLA-DP affects the donor selection strategy. Haplotype study of a large sample size using NGS identified linkage haplotypes beyond the 5 loci. LD, recombination events, and haplotype variation caused by DP loci emphasized that HLA 9-locus haplotype matching should be considered in donor selection, particularly the effect of DP loci. The finding lays the foundation for further studies on the effect of HLA-DP mismatch on transplantation.

Population-specific criterion to distinguish killer cell immunoglobulin-like receptor genotypes and haplotypes in a large Eastern Han population.

With the goal of improving the population-specific criteria to distinguish KIR genotypes and haplotypes in the region, we examined the KIR gene and haplotype data of Eastern Han based on a large population and analyzed the component genes of centromeric (Cen) and telomeric (Tel) KIR haplotype segments, which may differ in the protection they provide in hematopoietic stem cell transplantation. Samples from 598 families and 2845 unrelated individuals of Eastern Han origin were collected between 2010 and 2017. Genotyping of 17 KIR genes was performed by PCR-SSP and SSO methods. The results showed we obtained the KIR gene distribution of the Eastern Han population. The KIR gene frequencies (GF) in the present study are similar to those observed in other studies on Han but different from other populations. We observed a total of 56 different genotypes, including 1 AA and 55 group B genotypes. The high-frequency KIR genotype profiles found in the present population were consistent with other studies on Han populations but different from those conducted on other populations. In the family panel, a total of 28 KIR haplotypes were identified in the segregation study. The majority of Eastern Han carried group A KIR gene motifs. Comparison of the frequencies of Cen and Tel KIR gene motifs shows that they differ from other populations. The study on the distribution of KIR genes in the population may aid in the development of a complementary population-specific criterion to distinguish between KIR haplotypes and offer a research direction for further gene functional studies.

[The role of different KIR haplotypes in haplo-identical hematopoietic stem cell transplantation].

OBJECTIVE: To investigate the role of different immunoglobulin- like receptor (KIR)haplotypes in haplo- identical hematopoietic stem cell transplantation (HSCT). METHOD: Killer cell KIR genotyping was performed on 468 individuals from 156 unrelated families by PCR-SSP. A total of 624 KIR haplotypes from the parents were used for haplotype analysis. Ninety-two patients received haplo-identical HSCT from one of the parents. RESULTS: The family study showed segregation of one A haplotype and at least 20 unique B haplotypes. The frequency of haplotype A was 72.92% (455/624). The most commonly observed haplotypes in group B were B1, B2, and B3, present at a frequency of 10.26%, 5.77%, and 4.48%, respectively. Compared to KIR gene matched donors (n=17), grafts from KIR gene mismatched donors (n= 14) had a positive effect on survival after haplo- identical HSCT for AML/MDS patients (OS: 88.2%vs 42.9%,P=0.015; RFS: 88.2%vs 35.7%,P=0.007). No effect was observed for ALL/NHL patients (OS: 76.0%vs 75.0%,P=0.727; RFS: 68.0%vs 65.0%,P=0.866). A significantly lower survival rate was observed for transplants from AA (n=52) and AB1/AB2 donors (n=15), compared to other group Bx donors (n=25) (OS: 53.3%vs 96.0%,P=0.017; RFS: 53.3%vs 92.0%,P=0.019). Meanwhile, the risk of relapse was much higher in AA group (n=52) compared to Bx group (n=40) (25.0%vs 5.0%,P=0.009). A higher risk of TRM was observed in AB1/AB2 group (P=0.012). In addition, transplant from donors carried Cen-B was associated with an increased survival compared with Cen-A homozygous donors (OS: 94.7%vs 68.5%,P=0.036; RFS: 89.5%vs 64.4%,P=0.045). CONCLUSION: Overall, KIR genotyping and haplotype analyses should be useful for selection of the most optimal donors with favorable KIR gene grafts. KIR gene mismatch donors should be preferred for AML/MDS patients. Selecting donors carried Cen- B and avoiding the selection of donors of KIR genotype AA/AB1/AB2 was strongly advisable for haplo-identical HSCT.

Donor Killer Immunoglobulin-Like Receptor Profile Bx1 Imparts a Negative Effect and Centromeric B-Specific Gene Motifs Render a Positive Effect on Standard-Risk Acute Myeloid Leukemia/Myelodysplastic Syndrome Patient Survival after Unrelated Donor Hematopoietic Stem Cell Transplantation.

Donor killer immunoglobulin-like receptor (KIR) group B profiles (Bx) and homozygous of centromeric motif B (Cen-B/B) are the most preferable KIR gene content motifs for hematopoietic stem cell transplantation (HSCT). The risk of transplant from Bx1 donors and the benefit of the presence of Cen-B (regardless of number) were observed for standard-risk acute myeloid leukemia/myelodysplastic syndrome (AML/MDS) patients in this 4-year retrospective study. A total of 210 Chinese patients who underwent unrelated donor HSCT were investigated. Donor KIR profile Bx was associated with significantly improved overall survival (OS; P = .026) and relapse-free survival (RFS; P = .021) and reduced nonrelapse mortality (NRM; P = .017) in AML/MDS patients. A significantly lower survival rate was observed for transplants from Bx1 donors compared with Bx2, Bx3, and Bx4 donors for patients in first complete remission (n = 82; OS: P = .024; RFS: P = .021). Transplant from donors with Cen-B resulted in improved OS (HR = .256; 95% CI, .084 to .774; P = .016) and RFS (HR = .252; 95% CI, .084 to .758; P = .014) in AML/MDS patients at standard risk. However, this particular effect did not increase with a higher number of Cen-B motifs (cB/B versus cA/B; OS: P = .755; RFS: P = .768). No effect was observed on high-risk AML/MDS, acute lymphoblastic leukemia/non-Hodgkin lymphoma, and chronic myelogenous leukemia patients. Avoiding the selection of HSCT donors of KIR profile Bx1 is strongly advisable for standard-risk AML/MDS patients. The presence of the Cen-B motif rather than its number was more important in donor selection for the Chinese population.

Dynamic Detection of Anti-Human Leukocyte Antigen (HLA) Antibodies but not HLA-DP Loci Mismatches Can Predict Acute Graft-versus-Host Disease and Overall Survival in HLA 12/12-Matched Unrelated Donor Allogeneic Hematopoietic Stem Cell Transplantation for Hematological Malignancies.

The National Marrow Donor Program and Center for International Blood and Marrow Transplant Research provided guidelines for the use of anti-HLA antibodies and HLA-DP-mismatched loci in unrelated donor hematopoietic stem cell transplantation (HSCT). However, a deeper understanding of other potentially useful biomarkers for predicting clinical outcomes in HLA-A, -B, -C, -DRB1, -DQB1, and -DQA1 (12/12)-matched unrelated donor HSCT is needed to further improve clinical outcomes. We tested HLA genotyping for 123 pairs of patients and donors. Anti-HLA antibodies using the Luminex method was applied to 123, 117, and 106 serum samples collected before and 1 month and 3 months after transplantation. The presences of anti-HLA antibodies at the 3 time points were 37.4% (46 of 123), 40.2% (47 of 117), and 22.6% (24 of 106). Mismatch of HLA-DPB1 and/or DPA1 allele between patient-donor pairs was 83.6% (92 of 110). Patients with anti-HLA antibodies had delayed platelet recovery. The presence of anti-HLA antibodies and their dynamic changes after transplantation were associated with increased occurrence of grades II to IV acute and chronic graft-versus-host disease (GVHD), higher treatment-related mortality, and reduced overall survival (OS) and disease-free survival, especially in acute myeloid leukemia and myelodysplastic syndrome patients. Multivariate analysis showed that presence of anti-HLA antibodies before transplantation was a risk factor for GVHD and OS. Furthermore, HLA-DP loci-matched subgroup showed a trend towards a lower rate of acute GVHD and a higher OS in the anti-HLA Abs-negative group. Our results suggest that dynamic changes of anti-HLA antibodies independently predict for a negative outcome of HSCT, independent of HLA-DP loci mismatches. Routine monitoring for anti-HLA antibody dynamics should be conducted before and after HSCT.

Pre-existing anti-HLA antibodies negatively impact survival of pediatric aplastic anemia patients undergoing HSCT.

Graft failure and survival are the major problems for patients with aplastic anemia undergoing hematopoietic stem cell transplantation (HSCT). Previous studies showed that anti-HLA antibodies negatively impact engraftment in HSCT. This retrospective study of 51 pediatric patients with acquired aplastic anemia who underwent allogeneic HSCT at a single institution between 2006 and 2012 investigated the influence of anti-HLA antibodies on the outcome of HSCT. Serum samples collected before HSCT were tested for the presence of anti-HLA antibodies. Pre-existing anti-HLA antibodies were detected in 54.9% (28/51) of patients, among whom 39.2% (20/51) had anti-HLA class I antibodies. Anti-HLA antibodies were associated with worse five-yr survival (78.6% vs. 100%, p = 0.021) and higher treatment-related mortality (21.4% vs. 0%, p = 0.028) compared with antibody-negative patients. Anti-HLA class I antibody-positive patients had poorer five-yr survival (75.0%) than anti-HLA class I&II antibody-positive and antibody-negative patients (87.5% and 100.0%, respectively, p = 0.039). Presence of anti-HLA class I antibodies (p = 0.024) and older age (10 yr or more; p = 0.027) significantly increased the risk of post-HSCT mortality. Pre-existing anti-HLA antibodies negatively affect the outcome of HSCT in pediatric patients with aplastic anemia. Routine testing for anti-HLA antibodies concurrent with efficient treatment should be conducted prior to HSCT.

[Application of high resolution HLA typing in unrelated umbilical cord blood transplantation].

This study was purposed to investigate the clinical value of HLA matching(low and high resolution) and its effect on outcome of the patients received umbilical cord blood transplantation(UCBT). Sequence-specific oligonucleotide probe (SSOP) , sequence-based typing (SBT) and sequence-specific primers(SSP) were used to perform high resolution HLA matching for HLA-A, -B, -Cw, -DRB1, -DQB1 and low resolution for HLA-A, B, DRB1 among 34 patients with hematologic malignancies who received unrelated UCB transplantation and grafts. The effects of HLA matching (low or high resolution ) on leading engraftment, hematopoietic reconstitution, graft-versus-host disease (GVHD) and infection after UCB transplantation were analyzed by comparison. The results showed that the median of total nucleated cells (TNC) of transplanted cord blood was 6.0×10(7)/kg, The time of neutrophil recovery was significantly shortened when more than 5×10(7)/kg TNC were transplanted (P < 0.05). The HLA-(6-10)/10 group of high resolution HLA matching was better than the HLA (4-5)/10 group in the respect of leading engraftment, the time of platelet recovery and the rate of acute GVHD (P < 0.05). In contrast, HLA-I+II locus, HLA-DRB1 or HLA-DQB1 locus mismatch could prolong the platelet engraftment time (P < 0.05). There was statistical difference in the time of platelet recovery, the rate of acute GVHD between the HLA (5-6)/6 group of low resolution HLA matching and the HLA (3-4)/6 group after UCB transplantation (P < 0.05), but the mismatch locus of HLA with low resolution did not correlate with the time of platelet recovery (P > 0.05). It is concluded that the high resolution HLA matching between patients received unrelated UCB transplantation and grafts may contribute to select the better UCB, that has important clinical value to promote hematopoietic reconstitution and to reduce the complications after UCB transplantation.

[The characteristics of frequency distribution of KIR2DL1 alleles polymorphism and recognition HLA-C ligand in the Chinese Han population].

OBJECTIVE: To find out the distributed characteristics of KIR2DL1 alleles frequencies and the recognition HLA-C ligand in the Chinese Han population. METHODS: The 111 patients and 116 donors from CMDP were performed the KIR2DL1 high-resolution typing and KIR genotyping using sequence-based testing (SBT) and PCR-SSP methods. RESULTS: A total of 224 individuals with KIR2DL1 locus was predominantly observed and accounted for 98.68% (224/227). There were 3 different KIR2DL1 alleles, including KIR2DL1*00302, *00201 and *00401 alleles polymorphism. The most common phenotype observed were KIR2DL1*00302 (84.82%, 380/448), KIR2DL1*00201 (12.05%, 54/448) and KIR2DL1*00401(3.13%,14/448), present at allele genotype frequencies of 61.04%,6.22% and 1.58% respectively. The allele homozygotic types of KIR2DL1*00302 and KIR2DL1*00302 were the most frequent in 6 KIR2DL1 allele by high resolution typing. The allele heterozygous types of KIR2DL1*00302 and KIR2DL1*00401 presented statistically different in haplotypes A/A and B/x (P=0.001), and KIR2DL1*00401 lacked of all A/A haplotype. The KIR2DL1*00302 and KIR2DL1*00201 allele had significant positive associations between different KIR pairs of KIR2DS1, KIR2DL3, KIR2DS4 and KIR3DL1/S1 using linkage disequilibrium analysis (P<0.01), respectively. In the receptor-ligand of KIR/HLA model after allo-HSCT, KIR2DL1*00302 alleles correlated with their HLA-C2 group ligands. KIR2DL1*00302 and HLA-C*06:02 was the most common combination ligand model, but KIR2DL1*00302 and HLA-C*01:02 was the most frequent mismatch ligand model with the development of NK cell-induced alloreactivity, meanwhile there was statistically significant difference of frequency distribution (P<0.05). CONCLUSION: The KIR2DL1*00302 was the most frequent allele in Chinese Han population. The KIR2DL1 high resolution typing would be beneficial for predicting donor NK cells all activity after hematopoietic stem cell transplantation and selecting suitable donors.

Anti-human leukocyte antigens and anti-major histocompatibility complex class I-related chain A antibody expression in kidney transplantation during a four-year follow-up.

BACKGROUND: Humoral immunity is an important factor for long-term survival of renal allograft. Here we performed a four-year follow-up to explore the clinical significance of monitoring anti-human leukocyte antigens (HLA) and anti-major histocompatibility complex class I-related chain A (MICA) antibody expression after kidney transplantation. METHODS: We obtained serial serum samples from 84 kidney transplant patients over a four-year period. All patients were followed up at least 6 months after transplantation and had at least two follow-up points. Anti-HLA and anti-MICA antibody titres and serum creatinine (SCr) levels were evaluated at each follow-up. Patients were divided into 4 groups: HLA(+) MICA(-), HLA(-)MICA(+), HLA(+)MICA(+) and HLA(-)MICA(-). The impact of post-transplant antibody level on kidney allograft function was evaluated. RESULTS: Antibodies were detected in 38.1% (32/84) of the renal allograft recipients. HLA, MICA and HLA+MICA expression was observed in 18.89%, 14.44% and 5.93% of the recipients respectively. The most frequent anti-HLA and anti-MICA specific antibodies identified were A11, A24, A29, A32, A33, A80; B7, B13, B37; DR17, DR12, DR18, DR52, DR53, DR1, DR4, DR9, DR51; DQ7, DQ4, DQ8, DQ2, DQ9, DQ5, DQ6 and MICA02, MICA18, MICA19, MICA07, MICA27. As the time after transplantation elapsed, more recipients developed de novo antibody expression. Total 11.91% (10/84) of the recipients had de novo antibody expression during the follow up. The average level of SCr and the percentage of recipients with abnormal allograft function were significantly higher in recipients with anti-HLA and/or anti-MICA antibody expression than those without. The appearance of anti-HLA and anti-MICA antibody expression always preceded the increase in SCr value. CONCLUSIONS: Anti-HLA and anti-MICA antibody expression has predictive value for early and late allograft dysfunction. The presence of donor specific antibody is detrimental to graft function and graft survival.

Immune function assay (ImmuKnow) as a predictor of allograft rejection and infection in kidney transplantation.

BACKGROUND: The Cylex ImmuKnow (IK) assay provides a rapid and quantitative assessment of T-cell-mediated immune function. Studies have shown correlations between ImmuKnow assay and adverse events, such as immunosuppression and low or high calcineurin inhibitor trough levels. We investigated the correlation between IK changes and rejection or infection in kidney transplant patients and studied the potential application of the IK assays in optimizing individual immunosuppressive therapy. METHODS: ImmuKnow assay was used to determine dynamic intracellular ATP changes in CD4 cells in 193 samples from 42 kidney transplant patients and 25 healthy subjects. Patients were categorized into rejection, infection, and event-free groups. The IK values were assayed and analyzed between kidney transplant patients and healthy controls. RESULTS: Most IK values fell between 200 and 599 ng/mL from pre-transplantation to 30 months post-transplantation. The mean IK values continuously increased throughout 30 months. Incidental allograft rejection patients had significantly higher IK values compared with the event-free patients and controls. However, infection patients had significantly lower IK values. Seven days after treatment, IK values in rejection/infection patients were different compared with the values in autograft patients, and there was a significant correlation between calcineurin inhibitor (FK506) trough levels and IK values in rejection/infection patients. Serum creatinine levels in the rejection patients were significantly higher than those in the event-free patients, and C-reactive protein levels were significantly higher in the infection patients compared with the event-free patients. CONCLUSIONS: The IK assay combined with other biomarkers can be used to identify kidney transplant patients at high risk of rejection and infection.

[The impact of HLA high resolution typing mismatching of donor-recipient pairs on outcome of unrelated donor hematopoietic stem cell transplantation].

OBJECTIVE: To study the impact of various human leukocyte antigen (HLA) high resolution typing mismatching of donor-recipient pairs on prognosis of unrelated donor hematopoietic stem cell transplantation. METHODS: 835 donor-recipient pairs of CMDP data from 2005 to 2010 were analyzed retrospectively. HLA-A, B, C, DRB1 and DQB1 typing were performed using SBT, SSOP and SSP methods. The diseases involved in acute myeloid leukemia (AML) (n = 288), acute lymphoid leukemia (ALL) (n = 227), chronic myeloid leukemia (CML) (n = 187), myelodysplastic syndrome (MDS) (n = 52), non-hodgkin's lymphoma(NHL) (n = 25), aplastic anemia(AA) (n = 42) and thalassemia (n = 14). Of 835 donor-recipient pairs, 362 were completely matched, 159 had a mismatch for a single allele, 125 had a mismatch for a single antigen, 95 had mismatched for both single allele and single antigen, 29 were mismatched at double allele, 20 at double antigen, 45 at multiple allele and antigen. The follow-up assessment was completed before March 2011. RESULTS: HLA-matched pairs had higher overall survival (OS) than HLA-mismatched pairs (79.83% vs 73.15%), but there was no statistically significant differences (P > 0.05). HLA mismatch for a single allele plus a single antigen was a significantly risk factor for OS, disease free survival (DFS) and transplant-related mortality (TRM). The OS from high to low in different diseases were thalassemia, AA, CML, MDS, AML, NHL, and ALL. OS of HLA locus mismatch were DRB1 (94.4%), DQB1 (83.3%), B (75%), A (74.4%) and C (71.4%), respectively. OS of single allele mismatch at HLA locus from high to low were DRB1, C, A, B and DQB1.HLA-A, B, C locus mismatch were statistically significantly associated with lower OS and grade II-IV acute GVHD compared with HLA-matched pairs (P < 0.05). The donor-recipient pairs with HLA-B*15:01/B*15:05, DRB1*12:01/DRB1*12:02, C*04:01/C*03:04, DQB1*03:02/DQB1*03:03 alleles mismatch were given priority. But the donor-recipient pairs with HLA-B*39:01/B*39:05, C*15:02/C*14:02, C*08:01/C*03:04, C*07:02/C*15:02 alleles mismatch were risk factors for influence of OS and aGVHD. CONCLUSION: The high resolution typing for HLA-A, B, C, DRB1, DQB1 can be identified nonpermissive mismatch, which is beneficial for the selection of a suitable donor improves survival on unrelated donor HSCT.

Common and well-documented (CWD) alleles of human leukocyte antigen-A, -B, -C, -DRB1, and -DQB1 loci for the Chinese Han population do not quite correlate with the ASHI CWD alleles.

Human leukocyte antigen (HLA), which is extremely polymorphic, plays an important role in stem cell transplantation. The Chinese Han comprise a large population of approximately 1.3 billion with diverse HLA alleles that need to be characterized. Data from 3,296 independent, unrelated Chinese Han individuals (1,457 recipients and 1,839 donors) were provided by the China Marrow Donor Program (CMDP) for donor-recipient confirmatory typing. Sequence-based typing, sequence-specific oligonucleotide probe (SSOP)/High Definition-SSOP, and sequence-specific primer methods were used to obtain 4-digit alleles. A total of 49, 86, 50, 63, and 24 HLA-A, -B, -C, -DRB1, and -DQB1 alleles were observed. Following American Society for Histocompatibility and Immunogenetics (ASHI) common and well-documented (CWD) criteria, CWD alleles for Chinese Han in our laboratory test and other laboratory reports do not quite correlate with the ASHI CWD alleles: A*11:53, A*02:34, A*02:53N, B*27:24, B*46:02, B*55:12, C*01:06, C*03:17, C*06:06, C*07:66, C*07:67, C*08:22, DRB1*12:10, DQB1*03:13, and DQB1*06:05 are CWD, but are not included in the ASHI CWD list. A series of alleles are well-documented alleles and are listed in the ASHI CWD list. Conversely, A*26:03, B*51:03, C*12:05, C*15:09, C*15:11, C*17:03, DRB1*11:07, DRB1*11:11, DRB1*13:05, DRB1*13:13, DRB1*14:06, DRB1*14:12, DRB1*14:22, DRB1*14:25, and DQB1*06:11 are rare alleles, but are included in the ASHI CWD list. HLA ethnic diversity is the main reason for the differences in HLA alleles worldwide. The ASHI HLA CWD alleles help reduce the workload and expenses in high-resolution donor registries and the HLA allele frequencies provide a basis from which to predict the chances of finding HLA matching donors. Our data will be meaningful for the CMDP, for other worldwide donor registries, and for an updated ASHI CWD allele list.

[A study on allele frequencies and mismatching proportion of HLA-A, B, Cw, DRB1 and DQB1 on high-resolution donor-recipient typing in Chinese Han population].

OBJECTIVE: To analyze the allele frequencies and polymorphism of human leukocyte antigens (HLA) -A, B, Cw, DRB1 and DQB1 between donors-recipients on high-resolution typing; and to analyze the matching and mismatching proportion between donors and recipients. METHODS: HLA high-resolution types were determined by sequence based typing (SBT), sequence specific oligonucleotide probe (SSOP) and sequence specific primer (SSP) on 2540 unrelated Chinese Han individuals including 1168 recipients and 1372 donors, then statistical analyses were carried out. RESULTS: Forty-four HLA-A alleles were detected, and among them the frequencies of A*1101, A*2402, A*0201, A*0207, A*3303, A*0206 and A*3001 exceeded 0.05, and accounted for 80.4%. Eighty-one HLA-B alleles were detected, and the frequencies of B*4001, B*4601, B*5801, B*1302 and B*5101 exceeded 0.05, and accounted for 43.0% of total. There were 44 HLA-Cw alleles, among them the frequencies of Cw*0702, Cw*0102, Cw*0304, Cw*0801, Cw*0602, Cw*0303, Cw*0302 and Cw*0401 exceeded 0.05, and were 80.3% of total. There were 61 HLA-DRB1 alleles, the frequencies of DRB1*0901, DRB1*1501, DRB1*1202, DRB1*0803, DRB1*0701, DRB1*0405, DRB1*0301 and DRB1*1101 exceeded 0.05, and were 70.1% of total. Finally, 22 HLA-DQB1 alleles were detected, the frequencies of DQB1*0301, DQB1*0303, DQB1*0601, DQB1*0602, DQB1*0202, DQB1*0302, DQB1*0401, DQB1*0502 and DQB1*0201 exceeded 0.05, and they were 87.4% of total. All the five loci were of heterozygote deficiency. The HLA-A, B and DRB1 loci conformed to Hardy-Weinberg equilibrium (HWE) (P > 0.05); but HLA-Cw and HLA-DQB1 loci did not (P < 0.05). Except several particular genotypes, all the five loci conformed to HWE. After comparing data between donors and recipients, only 22.4% of recipients found HLA matched donors (10/10); 24.6% of recipients found single HLA allele mismatched donors (9/10); 26.3% of recipients had two HLA alleles mismatched donors (8/10). CONCLUSION: The characteristics of allele frequencies and polymorphism of HLA-A, B, Cw, DRB1 and DQB1 on high-resolution typing in Chinese Han population is valuable for donor searching in unrelated hematopoietic stem cell transplantation, and it provides genetic basis for donor registry and usage of donor resource for Chinese Marrow Donor Program.

[The impact of KIR2DS4 gene on clinical outcomes of HLA matched unrelated allo-HSCT].

OBJECTIVE: To detect the frequencies of KIR2DS4 alleles in Chinese Han population and to study the impact of KR2DS4 alleles on clinical outcomes of HLA identical unrelated allo-HSCT. METHODS: A Sequence-Based Testing (SBT) and TOPO TA cloning system for identifying and distinguishing alleles of the KIR2DS4 gene were established. A total of 150 Chinese-Han individuals, including 75 leukemia patients who received allo-HSCT and their HLA high-resolution typing identical unrelated donors (URD) were entered this study. The patients underwent transplantation for CML (n = 24), AML (n = 19), ALL (n = 29) and other malignancies (n = 3). RESULTS: The majority (139) of the 150 samples (92.7%) were positive for KIR2DS4. Sequencing of the whole length coding region of this gene identified four of the 12 known KIR2DS4 alleles, KIR2DS4*00101, *003, *004, and *007. 2DS4*00101 was the most frequent, being found in 109 of the 139 individuals (78.4%). The ratio of deleted to non-deleted versions of KIR2DS4 was approximately 1:2. Three novel KIR2DS4 alleles were identified. Transplantations from KIR haplotype B/x donors showed significantly higher overall survival rates than those from KIR haplotype A/A donors [RR 3.1 (95%CI 1.1 - 8.6), P = 0.007]. There was a lower overall survival rates in recipients when their donors carried two 2DS4 full-length allele (2DS4*001) than those carried less (0 or 1) 2DS4*001 allele (P = 0.031). In the haplotype A/A group, a higher risk of acute GVHD (aGVHD) [RR 9.0 (95%CI 1.2 - 66.9), P = 0.01], especially grade III-IV aGVHD (P = 0.006), was seen when the donor was homozygous for the full-length KIR2DS4*00101 allele. CONCLUSION: The development and application of the described SBT 2DS4 allele typing method highlights the diverse nature of the KIR gene family and displays the existence of KIR polymorphism that remains uncharacterized. Our findings suggest that KIR typing for 2DS4 be beneficial for selecting suitable donors.

Distribution of killer cell immunoglobulin-like receptor genes and 2DS4 alleles in the Chinese Han population.

Killer cell immunoglobulinlike receptors (KIRs) are a diverse family of receptors on natural killer cells. The KIR2DS4-deleted variant differs from the normal KIR2DS4 sequence by a 22-bp deletion in exon 5, which causes a frame shift, yielding a truncated KIR2DS4 protein with loss of the transmembrane and cytoplasmic domains of the full-length KIR2DS4 protein. A sequence-based testing and TOPO TA cloning system identifying and distinguishing alleles of the KIR2DS4 gene was established. The method was applied to 150 Chinese Han individuals: 75 patients who received T-depleted hematopoietic stem cells transplantation and their unrelated donors, establishing frequencies of 2DS4 allele and KIR gene within the local population. A majority (139) of the 150 samples (92.7%) were positive for KIR2DS4. The ratio of deleted to nondeleted versions of KIR2DS4 was approximately 1:2. Three KIR2DS4 novel alleles were identified. Forty-four percent individuals carried two group A haplotypes. The 17 KIR gene loci were found in 21.3%-100% in the population. Our findings suggest that the Chinese Han population is distinct in KIR gene frequencies and 2DS4 allele frequencies in comparison with some other populations.

[Relationship between CMV reactivation and KIR haplotype/HLA-Cw genotype in patients after unrelated-donor hematopoietic stem cell transplantation.].

OBJECTIVE: To explore the relationship between CMV reactivation and KIR haplotype or HLA-Cw genotype in patients after unrelated-donor hematopoietic stem cell transplantation (HSCT). METHODS: From January 2003 to December 2008 the HLA-Cw/KIR genotype of 48 patient-donor pairs were determined by polymerase chain reaction with sequence specific primers (PCR-SSP) and sequence specific nucleotide (PCR-SSOP). Posttransplant CMV reactivation was performed by immune histochemically assay. RESULTS: Of 48 patients, 15 were transplanted from unrelated donors with an antigen mismatch for HLA Cw and 33 patient-donor pairs were matched for HLA-Cw. The CMV reaction rate was 66.7% for HLA-Cw mismatch group and 48.5% for HLA-Cw match group (chi(2) = 1.39, P = 0.2375). Thirty-seven donor-patients pairs belonged to group C1 and 11 to group C2, and CMV reaction rate was 64.9% in group C1 and 18.2% in group C2 (chi(2) = 18.13, P < 0.0001). Twenty-six patients received graft from KIR haplotype A (group A donor) and 22 from KIR haplotype B donors (group B donor) and CMV reaction rate was 57.7% in group A donor and 50.0% in group B donor (chi(2) = 0.28, P = 0.5941). The number of donor activating KIRs (aKIRs) was less than that of recipient aKIRs in 34 patient-donor pairs in which the CMV reaction rate was 70.6%, and the number of donor aKIRs was more than that of recipient aKIRs in 14 patient-donor pairs in which the CMV reactivation was 14.3%. There was a significan difference between the two group (chi(2) = 12.44, P = 0.0004). CONCLUSION: KIR and HLA-Cw genotypes influence the rate of CMV reactivation following non-T cell deleted unrelated donor hematopoietic cell transplantation.